This invention relates to fire-resistant enclosures.
Fire resistant enclosures or fire safes normally comprise a metal structure lined with one or more layers of insulating matreial. With the advent of a requirement for protection against fire of valuable computer software stored on magnetic discs or tapes, the requirement of a fire safe is not merely to prevent combustion of the contents but also to prevent its temperature rising to a level where the stored data is destroyed. This can be much lower than a typical conmbustion temperature and requires new standards for fire resistance. Features such as additional layers of insulation, new insulation materials and wax containers which absorb heat on melting of the wax are all of assistance in improving the performance of fire resistant enclosures or fire safes. To achieve a high total performance from the fire resistant enclosure, corresponding improvements are needed in the effectiveness of door seals to prevent the passage of heat into the enclosure through the join between a door and the part of a casing defining a door opening. Door seals of sufficient performance tend to be complex in structure, adding substantially to the total cost of the product. Normal requirements also include a need for very close tolerances in the dimensions of the door and door opening and sealing elements which remain effective over a period of several years during which the door may be opened and closed several times per day.
An object of the invention is to provide a fire resistant enclosure with a door sealing arrangement which is both simple and effective and will remain so over the life of a product even if subject to wear and abuse.